Way to Grow
Solving the Challenges of Hillside Landscaping
by Steve & Cathy Lambert
T
here are many challenges when designing and installing landscapes in
Orinda, but one of the most prevalent is
our hilly terrain.
Because the need for hillside landscaping
is so common, there are plenty of creative
and proven solutions to choose from. The
best place to start is by writing down your
goals for the space. Is the slope within view
of your home and or yard making aesthetics
a priority? Do you need to alleviate erosion
problems? Do you want more flat space
for a vegetable or flower cutting garden?
Is there a need to expand your living or
recreation space?
The simplest solution for low-maintenance hillside landscaping is to plant the
whole hillside with species of groundcovers
or ornamental grasses that are well adapted
for slopes. If you like the look of grass and
your slope is not severe, buffalo grass or
fine-leaf fescues (no mow lawns), along
with some groupings of native Berkley
sedge, are good choices. For steeper slopes,
larger grasses will root deeper, along with
many natives like; cotoneaster, symporocarpus, and monkey flowers. There are also
numerous varieties of creeping groundcovers which root firmly enough to make them
a good hillside option.
For a more dramatic look plant your
slope with perennials and shrubs, which
vary in height, such as purple smokebush
(cotinus) with a foreground planting of cantaloupe torch lily (kniphophia). In shady
areas native brown twig dogwoods, along
with rhododendrons and azaleas work well.
Throw in a few foxgloves (digitalis) like
the new ‘apricot beauty’ for a long lasting,
blast of color.
For steeper hills, or areas that can’t be
graded easily, terracing can add more level
ground. The amount of terracing will of
coarse depends on the degree of slope
and the desired use for the space. One
approach is to build evenly spaced steps,
using pressure treated landscape timbers,
boulders, or other building material to
create step height walls. The flat areas can
then be used as individual beds, planted
with low-maintenance, cascading plants and
groundcovers.
Adding a walkway is a great way to take
advantage of a property with a view that
would otherwise not be enjoyed. However,
if you add a pathway to the top of your yard
you should always have a destination. This
can be something as simple as a bench or
something much more elaborate like a gazebo or sitting area with an arbor for shade
in the summer and a fireplace for warmth
in the winter.
Another option for a steeper hillside is
to create deeper terraces using retaining
walls. It’s surprising how much space can
be achieved with the addition of a small (less
than 30-inch high) retaining wall. These
retaining walls can be built using rock, steel
or pressure treated lumber.
Any retaining wall above three feet will
require engineering and city approval. They
are usually made using concrete (poured in
place), segmental concrete blocks, and concrete filled cinder block. Segmental block
such as Keystone can be very industrial
looking, but newer products such as Country
Manor Keystone or Belgard’s Celtic Wall,
are varying sized, colored concrete that is
tumbled for an antique stone look.
The availability of certain stone colors
and types changes fairly often. For a cooler
look we prefer the many shades of Connecticut Bluestone, and for warmer tones
our favorites are Oyster Thistle, Petrified
Forest Floor or Pioneer Stone. For a more
formal look, stones such as Bitter Root or
Kennesaw are good choices. There are also
stones from Asia that have been precut for
ease of installation. One of our best cost
saving techniques is to cap walls with stone
and then cover the face of the wall with a
fine Venetian plaster (stucco).
Grapevines have been planted on terraced hillsides for centuries but backyard
vineyards are a fairly recent trend. There
are now companies, such as the local Diablo
Vineyards, who will plant and maintain your
grapevines, pick and crush your grapes, and
STEVE LAMBERT
Steep slopes can be made picture perfect.
bottle your wine with a custom label for your
home grown varietal. Adding grapevines to
your landscape can add a wine country feel
and beautiful fall color.
Make your hillside a plus by adding a
recycling waterfall with or without a pond.
We’ve taken advantage of this natural gravitational force for many of our clients. A
waterfall will also allow you to broaden your
hillside plant palate to include water and
bog plants such as water hyacinths, water
lilies and irises.
A sunny, side yard hillside is a great spot
for a terraced vegetable or cutting flower
garden. You can use a less expensive material to install your retaining walls and can
enjoy the fruits (veggies and flowers) of your
labor without affecting your view.
When irrigating hillsides its important to
keep in mind the simple notion that water
flows down hill. We often find slopes where
the upper plant material is suffering from
lack of water while the plants at the bottom
are being overwatered. The two most effective and efficient ways to water a planted
hillside are traditional over head watering,
which should be adjusted to water above the
upper most plant material, and drip system
watering. When using drip, it’s critical that
you place all emitters above the plants on
the slope so that water moves into the plants
root zone, and not away from it. Which ever
method is used we find it beneficial to use
two or more cycle start times to give water
a chance to soak into the soil. To figure out
how long each cycle should run start your
irrigation and watch for run-off to start,
allow a short breather and then start the
second start time.
Hillside landscaping may involve more
work than landscaping a flat space, but the
end results are well worth it. If you have
any questions or need some advise on the
topic of hillside landscaping please feel
free to email us at [email protected].